R. Di Salvo
A5019693789- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Dark Matter and Cosmic Phenomena
- Nuclear physics research studies
- Atomic and Subatomic Physics Research
- Superconducting Materials and Applications
- Particle accelerators and beam dynamics
- Advanced X-ray Imaging Techniques
- Medical Imaging Techniques and Applications
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Radiation Detection and Scintillator Technologies
- Quantum, superfluid, helium dynamics
- Scientific Computing and Data Management
- Particle Detector Development and Performance
- Advanced NMR Techniques and Applications
- Cosmology and Gravitation Theories
- Distributed and Parallel Computing Systems
- Black Holes and Theoretical Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Noncommutative and Quantum Gravity Theories
- Atomic and Molecular Physics
University of Rome Tor Vergata
1998-2024
Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata
2009-2022
Istituto Nazionale di Fisica Nucleare, Sezione di Roma I
2010-2022
Istituto Nazionale di Fisica Nucleare, Sezione di Bari
2012-2016
Jagiellonian University
2015-2016
Institute of Physics
2015-2016
University of Bari Aldo Moro
2013-2014
Centre National de la Recherche Scientifique
2009-2012
Clermont Université
2009-2012
Norfolk State University
2011
The existence of a new force beyond the Standard Model is compelling because it could explain several striking astrophysical observations which fail standard interpretations. We searched for light vector mediator this dark force, $\mathrm{U}$ boson, with KLOE detector at DA$\Phi$NE $\mathrm{e}^{+}\mathrm{e}^{-}$ collider. Using an integrated luminosity 1.54 fb$^{-1}$, we studied process $\mathrm{e}^{+}\mathrm{e}^{-} \to \mathrm{U}\gamma$, $\mathrm{U} \mathrm{e}^{+}\mathrm{e}^{-}$, using...
We have searched for a light vector boson U, the possible carrier of "dark force", with KLOE detector at DAΦNE e+e− collider, motivated by astrophysical evidence presence dark matter in Universe. Using collisions collected an integrated luminosity 239.3 pb−1, we look dimuon mass peak reaction e+e−→μ+μ−γ, corresponding to decay U→μ+μ−. find no U signal. set 90% CL upper limit mixing parameter squared between photon and 1.6×10−5 8.6×10−7 region 520<mU<980 MeV.
The recent interest in a light gauge boson the framework of an extra U(1) symmetry motivates searches mass range below 1 GeV. We present search for such particle, dark photon, e+e−→Uγ, U→π+π− based on 28 million e+e−→π+π−γ events collected at DAΦNE by KLOE experiment. π+ π− production initial-state radiation compensates loss sensitivity previous U→e+e−, μ+μ− due to small branching ratios ρ–ω resonance region. found no evidence signal and set limit 90% CL mixing strength between photon ε2, U...
Neutral kaon pairs produced in phi decays anti-symmetric entangled state can be exploited to search for violation of CPT symmetry and Lorentz invariance. We present an analysis the CP-violating process phi->K_S K_L->pi+pi-pi+pi- based on 1.7 fb-1 data collected by KLOE experiment at Frascati phi-factory DAFNE. The are used perform a measurement CPT-violating parameters Delta_amu neutral kaons contest Standard Model Extension framework. measured reference frame fixed stars are: Delta_ao =...
We present new $\ensuremath{\Sigma}$ beam asymmetry data for $\ensuremath{\eta}$ meson photoproduction on the proton, using a novel tagged, laser backscattered, linearly polarized photon up to 1.1 GeV. The show large, positive asymmetries, at all incident energies. In addition ${S}_{11}(1535)$ and ${D}_{13}(1520)$ resonances necessary reproduce cross sections, ${P}_{13}(1720)$ ${D}_{15}(1675)$ ``four stars'' contribute observable, but cannot strong forward asymmetries measured energies...
The BGOOD photoproduction experiment accesses forward meson angles and low momentum exchange kinematics in the $uds$ sector, which may be sensitive to molecular-like hadron structure. Our results strangeness sector suggest a dominant role of meson-baryon dynamics. This includes structures $K^0\Sigma^0$, $K^+\Sigma^0$ $K^+\Sigma^0(1385)$ residing at $\Sigma^{(*)}K^{(*)}$ thresholds have an equivalence $P_C$ states $\Sigma_C^{(*)}\bar D^{(*)}$ thresholds. In non-strange baryon-baryon...
The double π0 photoproduction off the proton has been measured in beam energy range of 0.65–1.5 GeV. total and differential cross sections Σ asymmetry were extracted. section for first time third resonance region nucleon shows a prominent peak. interpretation these results by two independent theoretical models infers mostly selective excitation P11- D13-nucleon resonances.Received 17 January 2003DOI:https://doi.org/10.1103/PhysRevLett.90.222001©2003 American Physical Society
The possibility of anisotropies in the speed light relative to limiting electrons is considered. absence sidereal variations energy Compton-edge photons at European Synchrotron Radiation Facility's GRAAL facility constrains such representing first nonthreshold collision-kinematics study Lorentz violation. When interpreted within minimal standard-model extension, this result yields two-sided limit 1.6×10−14 95% confidence level on a combination parity-violating photon and electron...
The analysis of the γp→ηπ0p reaction has been performed using data from GRAAL experiment. total and differential cross sections beam asymmetry have obtained threshold up to 1.5 GeV energy. two resonances S11(1535) Δ(1700) are expected be excited in intermediate states this reaction. results used test predictions based on assumption that both dynamically generated meson-baryon interaction provided by chiral Lagrangians. term involving excitation, followed decay into ηΔ(1232), is found...
Using 1.6 fb−1 of e + − → ϕ ηγ data collected with the KLOE detector at DAΦNE, Dalitz plot distribution for η π 0 decay is studied world's largest sample ∼ 4.7 · 106 events. The density parametrized as a polynomial expansion up to cubic terms in normalized dimensionless variables X and Y . experiment sensitive all charge conjugation conserving expansion, including gX 2 term. statistical uncertainty parameters improved by factor two respect earlier measurements.
The differential cross section for the reaction p(γ,ηp) has been measured from threshold to 1100 MeV photon laboratory energy. For first time, region of S11(1535) resonance is fully covered in a photoproduction experiment and will allow precise extraction its parameters at point. These high precision data together with already beam asymmetry provide stringent constraints on new couplings baryon resonances η meson.
A measurement of the vector to pseudoscalar conversion decay $\phi \to \pi^0 e^+e^-$ with KLOE experiment is presented. sample $\sim 9500$ signal events was selected from a data set 1.7 fb$^{-1}$ $e^+e^-$ collisions at $\sqrt{s} \sim m_{\phi}$ collected DA$\Phi$NE collider. These were used obtain first transition form factor $| F_{\phi \pi^0}(q^2) |$ and new branching ratio decay: $\rm{BR}\,(\phi e^+e^-) = (\,1.35 \pm 0.05^{\,\,+0.05}_{\,\,-0.10}\,) \times 10 ^{-5}$. The result improves...
We have studied the vector to pseudoscalar conversion decay ϕ→ηe+e−, with η→π0π0π0, KLOE detector at DAΦNE. The data set of 1.7 fb−1 e+e− collisions s∼Mϕ contains a clear signal ∼31,000 events from which we measured value BR(ϕ→ηe+e−)=(1.075±0.007±0.038)×10−4. same sample is used determine transition form factor by fit invariant mass spectrum, obtaining bϕη=(1.28±0.10−0.08+0.09) GeV−2, that improves five precision previous measurement and in good agreement VMD expectations.
We searched for evidence of a Higgsstrahlung process in secluded sector, leading to final state with dark photon U and Higgs boson h', the KLOE detector at DAFNE. investigated case h' lighter than U, decaying into muon pair producing missing energy signature. found no set upper limits its parameters range 2m_mu<m_U<1000 MeV, m_h'<m_U.
The absolute branching ratio of the K+→π+π−π+(γ) decay, inclusive final-state radiation, has been measured using ∼17 million tagged K+ mesons collected with KLOE detector at DAΦNE, Frascati ϕ-factory. result is:BR(K+→π+π−π+(γ))=0.05565±0.00031stat±0.00025syst a factor ≃ 5 more precise respect to previous result. This work completes program precision measurements dominant kaon ratios KLOE.
We have carried out a new direct search for the CP violating decay KS -> 3pi0 with 1.7 fb^-1 of e+e- collisions collected by KLOE detector at phi-factory DAFNE. searched this in sample about 5.9 x 10^8 KL events tagging means interaction calorimeter and requiring six prompt photons. With respect to our previous search, analysis has been improved increasing factor four tagged more effective background rejection fake tags spurious clusters. find no candidates data simulated samples, while...
We have measured the running of effective QED coupling constant $\alpha(s)$ in time-like region $0.6<\sqrt s< 0.975$ GeV with KLOE detector at DA$\Phi$NE using Initial State Radiation process $e^+e^-\to\mu^+ \mu^-\gamma$. It represents first measurement this energy region. Our results show a more than 5$\sigma$ significance hadronic contribution to $\alpha(s)$, which is strongest direct evidence both time- and space-like regions achieved single measurement. By $e^+e^-\to\pi^+\pi^-$ cross...
$K^+\Lambda(1405)$ photoproduction has been studied at the BGOOD experiment via all neutral decay, $\Lambda(1405)\rightarrow\Sigma^0\pi^0$. The unique experimental setup allows both cross section and $\Lambda(1405)$ invariant mass distribution (line shape) to be measured over a broad $K^+$ polar angle range, extending extreme forward angles unattainable previous experiments. Evidence is provided for role of triangle singularity driven by $N^*(2030)$ resonance, which appears contribute...